<template>
  <div>
    <el-switch
      v-model="draggable"
      active-color="#13ce66"
      inactive-color="#ff4949">
    </el-switch>
    <el-button v-if="draggable" @click="batchSave">批量保存</el-button>
    <el-button type="danger" icon="el-icon-delete" circle @click="batchDelete"></el-button>
    <el-tree
      :allow-drop="allowDrop"
      :data="menus"
      :default-expanded-keys="expandedKey"
      :expand-on-click-node="false"
      :props="defaultProps"
      :draggable="draggable"
      node-key="catId"
      show-checkbox
      @node-drop="handleDrop"
      ref="menuTree"
    >
      <span
        class="custom-tree-node"
        slot-scope="{ node, data }"
      >
        <span>{{ node.label }}</span>
        <span>
          <el-button
            @click="() => append(data)"
            size="mini"
            type="primary"
            v-if="node.level != 3"
          >
            添加
          </el-button>
          <el-button
            @click="() => edit(data)"
            size="mini"
            type="success"
          >
            修改
          </el-button>
          <el-button
            @click="() => remove(node, data)"
            size="mini"
            type="danger"
            v-if="node.childNodes.length == 0"
          >
            删除
          </el-button>
        </span>
      </span>
    </el-tree>

    <el-dialog
      :close-on-click-modal="false"
      :title="title"
      :visible.sync="dialogVisible"
      width="30%"
    >
      <el-form :model="category">
        <el-form-item label="分类名称">
          <el-input
            autocomplete="off"
            v-model="category.name"
          ></el-input>
        </el-form-item>
        <el-form-item label="图标">
          <el-input
            autocomplete="off"
            v-model="category.icon"
          ></el-input>
        </el-form-item>
        <el-form-item label="计量单位">
          <el-input
            autocomplete="off"
            v-model="category.productUnit"
          ></el-input>
        </el-form-item>
      </el-form>

      <span
        class="dialog-footer"
        slot="footer"
      >
        <el-button @click="dialogVisible = false">取 消</el-button>
        <el-button
          @click="submitDate"
          dialogVisible="false"
          type="primary"
        >确 定</el-button>
      </span>
    </el-dialog>

  </div>
</template>

<script>
  export default {
    components: {},
    props: {},
    data () {
      return {
        draggable: false,
        pCid: [],
        updateNodes: [],
        maxLevel: 0,
        title: '',
        dialogType: '',
        category: {
          catId: null,
          name: '',
          parentCid: 0,
          productUnit: '',
          icon: '',
          catLevel: 0,
          showStatus: 1,
          sort: 0
        },
        menus: [],
        expandedKey: [],
        dialogVisible: false,
        defaultProps: {
          children: 'children',
          label: 'name'
        }
      };
    },
    methods: {
      submitDate () {
        if (this.dialogType === 'add') {
          this.addCategory();
        }
        if (this.dialogType === 'edit') {
          this.editCategory();
        }
      },
      batchDelete () {
        let catIds = [];
        let checkedName = [];
        let checkedNodes = this.$refs.menuTree.getCheckedNodes();
        console.log('被选中的元素', checkedNodes);
        for (let i = 0; i < checkedNodes.length; i++) {
          catIds.push(checkedNodes[i].catId);
          checkedName.push(checkedNodes[i].name);
        }
        this.$confirm(`此操作将永久删除【${checkedName}】菜单, 是否继续?`, '提示', {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        })
          .then(() => {
            this.$http({
              url: this.$http.adornUrl('/product/category/delete'),
              method: 'post',
              data: this.$http.adornData(catIds, false)
            }).then(({ data }) => {
              this.$message({
                type: 'success',
                message: '菜单批量删除成功!'
              });
              this.getMenus();
            });
          })
          .catch(() => {
            this.$message({
              type: 'info',
              message: '已取消删除'
            });
          });
      },
      batchSave () {
        this.$http({
          url: this.$http.adornUrl('/product/category/update/sort'),
          method: 'post',
          data: this.$http.adornData(this.updateNodes, false)
        }).then(({ data }) => {
          this.$message({
            message: '菜单顺序等修改成功',
            type: 'success'
          });
          // 刷新出新的菜单
          this.getMenus();
          // 设置需要默认展开的菜单
          this.expandedKey = this.pCid;
          this.updateNodes = [];
          this.maxLevel = 0;
          // this.pCid = 0;
        });
      },
      handleDrop (draggingNode, dropNode, dropType, ev) {
        console.log('handleDrop: ', draggingNode, dropNode, dropType);
        // 1、当前节点最新的父节点id
        let pCid = 0;
        let siblings = null;
        if (dropType == 'before' || dropType == 'after') {
          pCid = dropNode.parent.data.catId == undefined ? 0 : dropNode.parent.data.catId;
          siblings = dropNode.parent.childNodes;
        } else {
          pCid = dropNode.data.catId;
          siblings = dropNode.childNodes;
        }
        this.pCid.push(pCid);

        // 2、当前拖拽节点的最新顺序，
        for (let i = 0; i < siblings.length; i++) {
          if (siblings[i].data.catId == draggingNode.data.catId) {
            // 如果遍历的是当前正在拖拽的节点
            let catLevel = draggingNode.level;
            if (siblings[i].level != draggingNode.level) {
              // 当前节点的层级发生变化
              catLevel = siblings[i].level;
              // 修改他子节点的层级
              this.updateChildNodeLevel(siblings[i]);
            }
            this.updateNodes.push({
              catId: siblings[i].data.catId,
              sort: i,
              parentCid: pCid,
              catLevel: catLevel
            });
          } else {
            this.updateNodes.push({ catId: siblings[i].data.catId, sort: i });
          }
        }
        // 3、当前拖拽节点的最新层级
        console.log('updateNodes', this.updateNodes);
      },

      updateChildNodeLevel (node) {
        if (node.childNodes.length > 0) {
          for (let i = 0; i < node.childNodes.length; i++) {
            var cNode = node.childNodes[i].data;
            this.updateNodes.push({ catId: cNode.catId, catLevel: node.childNodes[i].level });
            this.updateChildNodeLevel(node.childNodes[i]);
          }
        }
      },
      allowDrop (draggingNode, dropNode, type) {
        // this.maxLevel = 0;
        // 1、被拖动的当前节点,以及拖动到指定节点的父节点的总层数不能大于3.

        // 1)、被拖动的节点总层数
        this.countNodeLevel(draggingNode);
        // 当前正在拖动的节点+拖动到指定父节点位置的深度不大于3即可

        let deep = Math.abs(this.maxLevel - draggingNode.level) + 1;
        console.log('深度: ', deep);
        if (type === 'inner') {
          return (deep + dropNode.level) <= 3;
        } else {
          // 被拖动节点的高度 + 目标节点的层数(深度) <=3 【高度+层数=根节点高度】(该树所有的节点的高度不能大于3)
          return (deep + dropNode.parent.level) <= 3;
        }
      },
      countNodeLevel (node) {
        // 找到所有子节点，求出最大深度
        if (node.childNodes != null && node.childNodes.length > 0) {
          for (let i = 0; i < node.childNodes.length; i++) {
            if (node.childNodes[i].level > this.maxLevel) {
              this.maxLevel = node.childNodes[i].level;
            }
            this.countNodeLevel(node.childNodes[i]);
          }
        }
      },
      // 获取菜单列表数据
      getMenus () {
        this.$http({
          url: this.$http.adornUrl('/product/category/list/tree'),
          method: 'get'
        }).then(({data}) => {
          console.log('成功获取到菜单数据...', data.data);
          this.menus = data.data;
        });
      },

      // 修改-初始化数据
      edit (data) {
        console.log('要修改的数据', data);
        this.dialogType = 'edit';
        this.title = '修改';
        this.dialogVisible = true;
        // 发送请求获取当前节点的最新的数据.
        this.$http({
          url: this.$http.adornUrl(`/product/category/info/${data.catId}`),
          method: 'get'
        }).then(({data}) => {
          // 请求成功
          console.log('要回显的数据', data);
          this.category.name = data.data.name;
          this.category.catId = data.data.catId;
          this.category.icon = data.data.icon;
          this.category.productUnit = data.data.productUnit;
          this.category.parentCid = data.data.parentCid;
          this.category.catLevel = data.data.catLevel;
          this.category.showStatus = data.data.showStatus;
          this.category.sort = data.data.sort;
        });
      },

      // 修改三级分类数据
      editCategory () {
        var {name, catId, icon, productUnit} = this.category;
        this.$http({
          url: this.$http.adornUrl('/product/category/update'),
          method: 'post',
          data: this.$http.adornData({name, catId, icon, productUnit}, false)
        }).then(({data}) => {
          this.$message({
            type: 'success',
            message: '菜单修改成功!'
          });
          // 保存成功关闭对话框
          this.dialogVisible = false;
          // 删除之后刷新菜单
          this.getMenus();
          // 设置删除之后展开当前删除的菜单节点
          this.expandedKey = [...this.expandedKey, this.category.parentCid];
        });
      },

      // 添加三级分类
      addCategory () {
        console.log('提交的三级分类数据', this.category);
        this.$http({
          url: this.$http.adornUrl('/product/category/save'),
          method: 'post',
          data: this.$http.adornData(this.category, false)
        }).then(({data}) => {
          this.$message({
            type: 'success',
            message: '菜单保存成功!'
          });
          // 保存成功关闭对话框
          this.dialogVisible = false;
          // 删除之后刷新菜单
          this.getMenus();
          // 设置删除之后展开当前删除的菜单节点
          this.expandedKey = [...this.expandedKey, this.category.parentCid];
        });
      },

      // 添加-初始化数据
      append (data) {
        console.log('append', data);
        this.dialogType = 'add';
        this.title = '添加';
        this.dialogVisible = true;
        this.category.parentCid = data.catId;
        this.category.catLevel = data.catLevel * 1 + 1;
        this.category.catId = null;
        this.category.name = '';
        this.category.icon = '';
        this.category.productUnit = '';
        this.category.showStatus = 1;
        this.category.sort = 0;
      },

      // 删除
      remove (node, data) {
        var ids = [data.catId];
        this.$confirm(`此操作将永久删除【${data.name}】菜单, 是否继续?`, '提示', {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        }).then(() => {
          this.$http({
            url: this.$http.adornUrl('/product/category/delete'),
            method: 'post',
            data: this.$http.adornData(ids, false)
          }).then(({data}) => {
            this.$message({
              type: 'success',
              message: '菜单删除成功!'
            });
              // 删除之后刷新菜单
            this.getMenus();
              // 设置删除之后展开当前删除的菜单节点
            this.expandedKey = [...this.expandedKey, node.parent.data.catId];
          });
        })
          .catch(() => {
            this.$message({
              type: 'info',
              message: '已取消删除'
            });
          });

        console.log('remove', node, data);
      }
    },
    created () {
      this.getMenus();
    }
  };
</script>

<style>
  .custom-tree-node {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 14px;
    padding-right: 8px;
  }
</style>


